feat: default worktrees under .git/wtp/worktrees with legacy warning

README.md

@@ -12,8 +12,8 @@ functionality with automated setup, branch tracking, and project-specific hooks.
 solution:** `wtp add feature/auth`
 
 wtp automatically generates sensible paths based on branch names. Your
-`feature/auth` branch goes to `../worktrees/feature/auth` - no redundant typing,
-no path errors.
+`feature/auth` branch goes to `.git/wtp/worktrees/feature/auth` - no redundant
+typing, no path errors.
 
 ### 🧹 Clean Branch Management
 
@@ -54,8 +54,8 @@ requirements.
 
 ### 📍 Instant Worktree Navigation
 
-**git-worktree pain:** `cd ../../../worktrees/feature/auth` (if you remember the
-path) **wtp solution:** `wtp cd feature/auth` with tab completion
+**git-worktree pain:** `cd .git/wtp/worktrees/feature/auth` (if you remember
+the path) **wtp solution:** `wtp cd feature/auth` with tab completion
 
 Jump between worktrees instantly. Use `wtp cd @` to return to your main
 worktree. No more terminal tab confusion.
@@ -127,20 +127,20 @@ sudo mv wtp /usr/local/bin/  # or add to PATH
 
 ```bash
 # Create worktree from existing branch (local or remote)
-# → Creates worktree at ../worktrees/feature/auth
+# → Creates worktree at .git/wtp/worktrees/feature/auth
 # Automatically tracks remote branch if not found locally
 wtp add feature/auth
 
 # Create worktree with new branch
-# → Creates worktree at ../worktrees/feature/new-feature
+# → Creates worktree at .git/wtp/worktrees/feature/new-feature
 wtp add -b feature/new-feature
 
 # Create new branch from specific commit
-# → Creates worktree at ../worktrees/hotfix/urgent
+# → Creates worktree at .git/wtp/worktrees/hotfix/urgent
 wtp add -b hotfix/urgent abc1234
 
 # Create new branch tracking a different remote branch
-# → Creates worktree at ../worktrees/feature/test with branch tracking origin/main
+# → Creates worktree at .git/wtp/worktrees/feature/test with branch tracking origin/main
 wtp add -b feature/test origin/main
 
 # Remote branch handling examples:
@@ -188,7 +188,7 @@ wtp uses `.wtp.yml` for project-specific configuration:
 version: "1.0"
 defaults:
   # Base directory for worktrees (relative to project root)
-  base_dir: "../worktrees"
+  base_dir: ".git/wtp/worktrees"
 
 hooks:
   post_create:
@@ -326,21 +326,21 @@ evaluates `wtp shell-init <shell>` once for your session—tab completion and
 
 ## Worktree Structure
 
-With the default configuration (`base_dir: "../worktrees"`):
+With the default configuration (`base_dir: ".git/wtp/worktrees"`):
 
 ```
 <project-root>/
 ├── .git/
+│   └── wtp/
+│       └── worktrees/
+│           ├── main/
+│           ├── feature/
+│           │   ├── auth/          # wtp add feature/auth
+│           │   └── payment/       # wtp add feature/payment
+│           └── hotfix/
+│               └── bug-123/       # wtp add hotfix/bug-123
 ├── .wtp.yml
 └── src/
-
-../worktrees/
-├── main/
-├── feature/
-│   ├── auth/          # wtp add feature/auth
-│   └── payment/       # wtp add feature/payment
-└── hotfix/
-    └── bug-123/       # wtp add hotfix/bug-123
 ```
 
 Branch names with slashes are preserved as directory structure, automatically

cmd/wtp/add.go

@@ -65,6 +65,12 @@ func addCommand(_ context.Context, cmd *cli.Command) error {
 		return err
 	}
 
+	errWriter := cmd.Root().ErrWriter
+	if errWriter == nil {
+		errWriter = os.Stderr
+	}
+	warnLegacyBaseDir(errWriter, mainRepoPath)
+
 	// Create command executor
 	executor := command.NewRealExecutor()
 

cmd/wtp/cd.go

@@ -57,16 +57,27 @@ func cdToWorktree(_ context.Context, cmd *cli.Command) error {
 	}
 
 	// Initialize repository to check if we're in a git repo
-	_, err = git.NewRepository(cwd)
+	repo, err := git.NewRepository(cwd)
 	if err != nil {
 		return errors.NotInGitRepository()
 	}
 
+	mainRepoPath, err := repo.GetMainWorktreePath()
+	if err != nil {
+		mainRepoPath = repo.Path()
+	}
+
 	// Get the writer from cli.Command
 	w := cmd.Root().Writer
 	if w == nil {
 		w = os.Stdout
 	}
+	errWriter := cmd.Root().ErrWriter
+	if errWriter == nil {
+		errWriter = os.Stderr
+	}
+
+	warnLegacyBaseDir(errWriter, mainRepoPath)
 
 	// Use CommandExecutor-based implementation
 	executor := command.NewRealExecutor()

cmd/wtp/cd_test.go

@@ -21,7 +21,7 @@ func TestCdCommand_AlwaysOutputsAbsolutePath(t *testing.T) {
 HEAD abc123
 branch refs/heads/main
 
-worktree /Users/dev/project/worktrees/feature/auth
+worktree /Users/dev/project/main/.git/wtp/worktrees/feature/auth
 HEAD def456
 branch refs/heads/feature/auth
 
@@ -42,13 +42,13 @@ branch refs/heads/feature/auth
 		{
 			name:          "feature worktree by branch name",
 			worktreeName:  "feature/auth",
-			expectedPath:  "/Users/dev/project/worktrees/feature/auth",
+			expectedPath:  "/Users/dev/project/main/.git/wtp/worktrees/feature/auth",
 			shouldSucceed: true,
 		},
 		{
 			name:          "feature worktree by directory name",
 			worktreeName:  "auth",
-			expectedPath:  "/Users/dev/project/worktrees/feature/auth",
+			expectedPath:  "/Users/dev/project/main/.git/wtp/worktrees/feature/auth",
 			shouldSucceed: true, // Directory-based resolution works as expected
 		},
 		{

cmd/wtp/init.go

@@ -69,7 +69,7 @@ version: "1.0"
 # Default settings for worktrees
 defaults:
   # Base directory for worktrees (relative to repository root)
-  base_dir: ../worktrees
+  base_dir: .git/wtp/worktrees
 
 # Hooks that run after creating a worktree
 hooks:

cmd/wtp/init_test.go

@@ -138,7 +138,7 @@ func TestInitCommand_Success(t *testing.T) {
 	// Check for required sections
 	assert.Contains(t, contentStr, "version: \"1.0\"")
 	assert.Contains(t, contentStr, "defaults:")
-	assert.Contains(t, contentStr, "base_dir: ../worktrees")
+	assert.Contains(t, contentStr, "base_dir: .git/wtp/worktrees")
 	assert.Contains(t, contentStr, "hooks:")
 	assert.Contains(t, contentStr, "post_create:")
 

cmd/wtp/legacy_warning.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+
+	"github.com/satococoa/wtp/v2/internal/config"
+)
+
+const (
+	legacyWarningMessage = "Warning: detected legacy worktrees directory at %s\n"
+	legacyConfigMessage  = "Set base_dir: \"../worktrees\" in %s to keep using it, or move worktrees to %s\n"
+)
+
+func warnLegacyBaseDir(errWriter io.Writer, repoRoot string) {
+	if errWriter == nil {
+		errWriter = os.Stderr
+	}
+
+	if config.FileExists(repoRoot) {
+		return
+	}
+
+	legacyBaseDir := filepath.Clean(filepath.Join(repoRoot, "..", "worktrees"))
+	info, err := os.Stat(legacyBaseDir)
+	if err != nil || !info.IsDir() {
+		return
+	}
+
+	entries, err := os.ReadDir(legacyBaseDir)
+	if err != nil || len(entries) == 0 {
+		return
+	}
+
+	newDefault := filepath.Clean(filepath.Join(repoRoot, config.DefaultBaseDir))
+	configPath := filepath.Join(repoRoot, config.ConfigFileName)
+
+	if _, err := fmt.Fprintf(errWriter, legacyWarningMessage, legacyBaseDir); err != nil {
+		return
+	}
+	if _, err := fmt.Fprintf(errWriter, legacyConfigMessage, configPath, newDefault); err != nil {
+		return
+	}
+}

cmd/wtp/legacy_warning_test.go

@@ -0,0 +1,83 @@
+package main
+
+import (
+	"bytes"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/satococoa/wtp/v2/internal/config"
+)
+
+func TestWarnLegacyBaseDir_WarnsWhenLegacyDirExistsAndNoConfig(t *testing.T) {
+	baseDir := t.TempDir()
+	repoRoot := filepath.Join(baseDir, "repo")
+	if err := os.MkdirAll(repoRoot, 0o755); err != nil {
+		t.Fatalf("failed to create repo root: %v", err)
+	}
+
+	legacyDir := filepath.Join(repoRoot, "..", "worktrees")
+	if err := os.MkdirAll(legacyDir, 0o755); err != nil {
+		t.Fatalf("failed to create legacy dir: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join(legacyDir, "placeholder"), []byte("x"), 0o644); err != nil {
+		t.Fatalf("failed to write placeholder: %v", err)
+	}
+
+	var buf bytes.Buffer
+	warnLegacyBaseDir(&buf, repoRoot)
+
+	output := buf.String()
+	if output == "" {
+		t.Fatalf("expected warning output, got empty string")
+	}
+	if !bytes.Contains(buf.Bytes(), []byte("legacy worktrees directory")) {
+		t.Errorf("expected warning message to mention legacy directory, got: %s", output)
+	}
+	if !bytes.Contains(buf.Bytes(), []byte(config.ConfigFileName)) {
+		t.Errorf("expected warning to mention config file, got: %s", output)
+	}
+}
+
+func TestWarnLegacyBaseDir_NoWarningWhenConfigExists(t *testing.T) {
+	baseDir := t.TempDir()
+	repoRoot := filepath.Join(baseDir, "repo")
+	if err := os.MkdirAll(repoRoot, 0o755); err != nil {
+		t.Fatalf("failed to create repo root: %v", err)
+	}
+
+	configPath := filepath.Join(repoRoot, config.ConfigFileName)
+	if err := os.WriteFile(configPath, []byte("version: 1.0\n"), 0o644); err != nil {
+		t.Fatalf("failed to write config: %v", err)
+	}
+
+	legacyDir := filepath.Join(repoRoot, "..", "worktrees")
+	if err := os.MkdirAll(legacyDir, 0o755); err != nil {
+		t.Fatalf("failed to create legacy dir: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join(legacyDir, "placeholder"), []byte("x"), 0o644); err != nil {
+		t.Fatalf("failed to write placeholder: %v", err)
+	}
+
+	var buf bytes.Buffer
+	warnLegacyBaseDir(&buf, repoRoot)
+
+	if buf.Len() != 0 {
+		t.Fatalf("expected no warning output, got: %s", buf.String())
+	}
+}
+
+func TestWarnLegacyBaseDir_NoWarningWhenLegacyMissing(t *testing.T) {
+	baseDir := t.TempDir()
+	repoRoot := filepath.Join(baseDir, "repo")
+	if err := os.MkdirAll(repoRoot, 0o755); err != nil {
+		t.Fatalf("failed to create repo root: %v", err)
+	}
+
+	var buf bytes.Buffer
+	warnLegacyBaseDir(&buf, repoRoot)
+
+	if buf.Len() != 0 {
+		t.Fatalf("expected no warning output, got: %s", buf.String())
+	}
+}

cmd/wtp/list.go

@@ -109,10 +109,16 @@ func listCommand(_ context.Context, cmd *cli.Command) error {
 	if w == nil {
 		w = os.Stdout
 	}
+	errWriter := cmd.Root().ErrWriter
+	if errWriter == nil {
+		errWriter = os.Stderr
+	}
 
 	// Load config to get base_dir
 	cfg, _ := config.LoadConfig(mainRepoPath)
 
+	warnLegacyBaseDir(errWriter, mainRepoPath)
+
 	// Resolve display options
 	opts := resolveListDisplayOptions(cmd, w)